How to get rid of the error: Error using horzcat. Dimensions of matrices being concatenated are not consistent.

I'm segmenting line from a document image using the following code. I want to store the segmented line in a folder from where i could use those individual images for recognition.

workspace;  % Make sure the workspace panel is showing.
fontSize = 14;

% Read in a standard MATLAB gray scale demo image.
folder = 'F:\SSN\project\Phase II\6th Review\Whole image\seg';
baseFileName = 'image_a.jpg';
% Get the full filename, with path prepended.
fullFileName = fullfile(folder, baseFileName);
grayImage = imread(fullFileName);
% Get the dimensions of the image.  
% numberOfColorBands should be = 1.
[rows, columns, numberOfColorBands] = size(grayImage);
if numberOfColorBands > 1
  % It's not really gray scale like we expected - it's color.
  % Convert it to gray scale by taking only the green channel.
  grayImage = grayImage(:, :, 2); % Take green channel.
end
% Display the original gray scale image.
subplot(2, 2, 1);
imshow(grayImage, []);
axis on;
title('Original Grayscale Image', 'FontSize', fontSize);
% Enlarge figure to full screen.
set(gcf, 'Units', 'Normalized', 'OuterPosition', [0 0 1 1]);
% Give a name to the title bar.
set(gcf, 'Name', 'Demo by ImageAnalyst', 'NumberTitle', 'Off') 

% Let's compute and display the histogram.
[pixelCount, grayLevels] = imhist(grayImage);
pixelCount(end) = 0; % Suppress spike so we can see shape.
subplot(2, 2, 2); 
bar(grayLevels, pixelCount);
grid on;
title('Histogram of original image', 'FontSize', fontSize);
xlim([0 grayLevels(end)]); % Scale x axis manually.

verticalProfile = mean(grayImage, 2);
subplot(2, 2, 3);
plot(verticalProfile);
% Find the white spaces
whiteGaps = verticalProfile > 250;
% Get the centroids of the white gaps
measurements = regionprops(whiteGaps, 'Centroid');
allCentroids = [measurements.Centroid];
centroidX = allCentroids(1:2:end);
centroidY = allCentroids(2:2:end);
% Now we have the lines to crop out.
% Make a new figure
binaryImage = grayImage < 125;
for k = 1 : length(centroidY)-1
  line1 = int32(centroidY(k));
  line2 = int32(centroidY(k+1));
  thisLine = binaryImage(line1:line2, :);
    thisLine=imresize(thisLine,[100 100]);
    imwrite(thisLine,['Datasets/',num2str(thisLine),'.jpg']);
  figure,
  imshow(thisLine);
  
end

[Azzi Abdelmalek]

Why all this code? just post the lines concerned with the error message

Answer 1

[Jos (10584)]

This is not going well:

thisLine=imresize(thisLine,[100 100]);
imwrite(thisLine,['Datasets/',num2str(thisLine),'.jpg']);

In the first line you create a 100-by-100 matrix with numbers. In the second line you convert this array to a string using num2str, apparently because you want a filename ...

thisLine = imresize(thisLine,[100 100]);
XXX = ... % what should be here?
filename = ['Datasets/' XXX '.jpg']
imwrite(thisLine, filename);